<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>

    <style>
        div{
          margin: 10px;
          padding: 5px;
          font-size: 12px;
          line-height: 2px;
        }
        #father{
            border: 1px solid black;
            padding: 0px;
        }
        #first{
            background-color: #FFCC70;
            border: 1px solid black;
            position: relative;  /*相对定位，上下左右*/
            top: -20px;  /*距离上面-20px个位置*/
            left: 20px;  /*距离左边20px个位置*/
        }
        #second{
            background-color: #f1ff70;
            border: 1px dashed #064f1b;
        }
        #third{
            background-color: #70a2ff;
            border: 1px solid red;
        }
    </style>

</head>
<body>

<div id="father">
  <div id="first">第一个盒子</div>
  <div id="second">第二个盒子</div>
  <div id="third">第三个盒子</div>
</div>

</body>
</html>